1,1'-アゾビス-1,2,3-トリアゾール:安定したN8構造と光色素性を持つ高窒素化合物
Yu-Chuan Li1, Cai Qi, Sheng-Hua Li
1School of Material Science & Engineering, State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, P.R. China.
Journal of the American Chemical Society
|August 19, 2010
まとめ
研究者らは,1-アミノ-1,2,3-トリアゾールから 1,1'-アゾビス-1,2,3-トリアゾールを合成した. 研究は,その構造,熱安定性,光色特性などを特徴づけた.
科学分野:
- 合成有機化学 合成有機化学とは
- マテリアルサイエンス 材料科学
背景:
- 1,2,3-トリアゾール誘導体は,多用途の化学的構成要素である.
- 新しい窒素に富んだ化合物の調査は,エネルギー材料と機能的なアプリケーションにとって非常に重要です.
研究 の 目的:
- 新種のアゾビストリアゾール化合物を合成し,特徴づけること.
- 合成された化合物の構造的,熱的,光色学的性質を調査する.
主な方法:
- 1-アミノ-1,2,3-トリアゾールとナトリウムジクロロアイソシアヌラートとの反応を含む化学合成.
- 構造の解明のためのX線結晶学分析.
- 熱安定性試験 (DSC/TGAなど)
- UV-Vis照射下でのフォトクロミック性質の調査.
主要な成果:
- 1,1'-アゾビス-1,2,3-トリアゾールの合成と分離が成功しました.
- 詳細な構造情報は,X線結晶学によって得られた.
- 熱分解行動の特徴付け. 熱分解行動の特徴付け.
- フォトクロミック行動の観察により,光に反応する潜在的な応用が示されました.
結論:
- 1,1′-アゾビス-1,2,3-トリアゾールは,興味深い光色特性を持つ,安定し,特徴づけられる化合物です.
- 合成経路は,アゾビストリアゾール化合物の新しいクラスへのアクセスを提供します.
- 材料科学と光化学におけるその応用に関するさらなる研究が必要である.
関連する概念動画
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.
Nomenclature of Aryl and Heterocyclic Amines
The simplest aromatic amine is phenylamine, which contains an –NH2 functionality directly attached to an aromatic ring. The name aniline is designated for this skeleton. As shown in Figure 1, the common names of the functionalized anilines involve prefixes ortho-, meta-, and para- to indicate the substitution position. Different functionalized aniline derivatives also have notable trivial names.
Structure of Amines
The hybridized nitrogen atom in amines possesses a lone pair of electrons and is bound to three substituents with a bond angle of around 108°, which is less than the tetrahedral angle of 109.5°. However, the C–N–H bond angle is slightly larger at 112°, with a carbon–nitrogen bond length of 147 pm. This carbon–nitrogen bond length of of amines is longer than the carbon–oxygen bond of alcohols (143 pm) but shorter than alkanes’ carbon–carbon bond (154 pm). These aspects are illustrated in Figure...
Basicity of Heterocyclic Aromatic Amines
Heterocyclic amines, where the N atom is a part of an alicyclic system, are similar in basicity to alkylamines. Interestingly, the heterocyclic amine having a nitrogen atom as part of an aromatic ring has much less basicity than its corresponding alicyclic counterpart. For this reason, as presented in Figure 1, piperidine (pKb = 2.8) is significantly more basic than pyridine (pKb = 8.8).
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism
Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.
Diazonium Group Substitution: –OH and –H
Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.


![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)